1. Technical Field
The present invention relates to a control system configured by a television receiver as a controlled apparatus, for example, and a remote control (hereinafter, remote) or the like as a control apparatus corresponding thereto, for example, and a controlled apparatus and a control apparatus adapted to the system. As an example, the invention relates to a control system that estimates a position of a viewer who has a high probability of being located in a location substantially the same as a position where a remote is present and enables adjustment to effects of video and sound so that they may be adapted to the position of the viewer, and a controlled apparatus and a control apparatus adapted to the system.
2. Related Art
Historically, an audio and visual apparatus with a function of remote control position detection has been proposed. According to the apparatus, a remote receives an acoustic wave signal from an audio and visual apparatus corresponding to the remote, converts a reception level as an acoustic wave detection signal into a remote control signal, and transmits the signal toward the audio and visual apparatus. The audio and visual apparatus receives the transmitted remote control signal and uses the reception level contained in the signal as a remote control signal detection signal, scans the orientation of a speaker and directed the speaker toward a direction in which the remote control signal detection signal indicates the maximum reception level. Further, the apparatus recognizes a distance to the remote based on timing of transmission and reception of the signal related to the remote in the direction and stores the recognized value as remote control position information point by point, uses remote control position information with highest frequency among the stored information as an initial position of the remote, and controls the orientation of the speaker based on the remote control position information containing the initial position (see JP-A-8-214183, paragraphs 0007 to 0015, FIGS. 4 and 5).
Also, in JP-A-8-214183, control adapted to the preference and habit of a user by considering clock information, calendar time information, program information, etc. other than the information of direction of the remote or distance thereto has been proposed.
Further, optimization of acoustic effect according to a position of a viewer has been proposed. According to the proposal, a television receiver includes infrared light receiving means, and plural light receiving elements having different directivities provided in the receiving means receive infrared light from a remote to detect a direction in which the remote (i.e., a person with the remote) is located from an incident direction of the received infrared light, and then, the television receiver adjusts the sound volume balance of right and left speakers based on the detection result (see JP-A-1-109867, the middle part of upper left column to the middle part of lower right column on the second page, FIG. 1).
Similarly, there has been a proposal in which a television receiver main body includes plural personal detection infrared sensors respectively having directivities in different directions provided at the lower part thereof, and detects a direction in which a remote (i.e., a person with the remote) is located from an incident direction of the received infrared light from the remote using these plural personal detection infrared sensors, and then, the television receiver adjusts the sound volume balance of right and left speakers based on the detection result (see JP-A-5-137200, paragraphs 0005 to 0007, FIG. 1).
The above described existing technologies still have the following various unsolved problems. That is, since all of the above described technologies disclosed in the documents are to determine the direction in which the remote is located by receiving the remote side emission of light at the television receiver side, they have potentials to inhibit power saving in the remote, which is typically arranged so as to operate using a small battery with low capacity as a power supply, and cause complication that the battery must be frequently replaced.
Further, in the technology proposed in JP-A-8-214183, since audible sound is used as an acoustic wave signal from the audio and visual apparatus, it is inevitable that the viewer has discomfort throughout the adjustment depending on the degree of the acoustic signal to be applied. Furthermore, in the proposals of JP-A-1-109867 and JP-A-5-137200, it is necessary to provide a large number of light receiving elements at the remote side to improve the precision of position detection, however, the large number of light receiving elements cause upsizing of the remote. If the number of light receiving elements is reduced, the resolution of position detection can not be secured.